1. Field of the Invention
The present invention relates to an electronic apparatus in which at least a light source and a light receiving element are arranged in parallel on a circuit substrate and light guides are interposed between this light source, light receiving element and a translucent panel provided on a front panel.
2. Description of the Related Art
Conventionally, a front panel of a television receiver or the like incorporates a plurality of embedded switches for processing and controlling various sections of the television receiver and is provided with a light receiving section which receives a light signal from a remote control device and a light-emitting display section which turns ON/OFF in conjunction with ON/OFF of a power supply, and when the light receiving section and light-emitting display section are made up of a single translucent panel, light guides for guiding a light signal from the remote control device and illumination light from a light source are arranged between the translucent panel and the light receiving element and between the translucent panel and the light source. Furthermore, when the light receiving element and the light source are arranged in parallel on the circuit substrate, if illumination light from the light source leaks out to the light receiving element, this may cause malfunction, and therefore it is necessary to shield the illumination directed from the light source to the light receiving element. For example, Japanese Patent Laid-Open Publication No. 2002-110003 (patent document 1) proposes a structure which is provided with a light guide for guiding illumination light and which shields light so as to prevent the illumination light from the light source from leaking out to parts other than the necessary part. This discloses a switch device provided with a circuit substrate including a panel body, a plurality of operation knobs having a translucent display section in a manner it can be pressed into this panel body, switch bodies arranged behind these operation knobs corresponding to the respective operation knobs and a light source which illuminates the display section, and a light guide disposed between this circuit substrate and the operation knobs for guiding the light from the light source to the display section, wherein the light guide extends in a direction adjacent to the respective operation knobs, the light source is placed on the side of the light guide and the perimeter of the light guide is covered with a white-color-based light-shielding cylindrical member so as to prevent the illumination light from the light guide from leaking out to at least parts other than the area corresponding to the display section.
The switch device described in the patent document 1 arranges a common continuous light guide in correspondence with a plurality of adjacent operation knobs, covers the perimeter of the light guide with the light-shielding cylindrical member except for the area which corresponds to the display section of the operation knobs to thereby shield illumination light which leaks out to the neighboring display section using the light-shielding cylindrical member. However, in the switch device shown in the patent document 1, all illumination light guided by the light guide is oriented toward the same direction, and therefore the light-shielding cylindrical member which covers the light guide has a relatively simple shape, but as described above, when the light receiving element and the light source for illumination display are mounted on the circuit substrate, the orientations of illumination light beams guided by the respective light guides arranged between the translucent panel and light source provided on the front panel are opposite to each other. That is, since the receiving side light guide placed between the translucent panel and the light receiving element guides the light signal from the remote control apparatus to the light receiving element, the light signal guided by the receiving side light guide is oriented from the translucent panel toward the light receiving element, while since the light emitting side light guide placed between the light source and the translucent panel guides illumination light from the light source to the translucent panel, the illumination light guided by the light emitting side light guide is oriented from the light source toward the translucent panel, and therefore it is not possible to use a simple light-shielding cylindrical member as described in the patent document 1 and its shape is more complicated. Moreover, the switch device described in the patent document 1 consists of the operation knobs, light guide and circuit substrate individually attached to the housing, which involves many parts to be assembled and requires complicated assembly work.